Novel spectrofluorometric method utilizing functionalized carbon quantum dots for determining histamine levels in nasal secretions: Implications for allergic rhinitis

Efficient and eco-friendly detection of gabapentin using nitrogen-doped carbon quantum dots: an analytical and green chemistry approach

This study presents the development of an eco-friendly and highly selective mitrogen-doped carbon quantum dot based sensor (N-CQDs) for the detection of gabapentin - a commonly misused drug. A detailed characterization of N-CQDs spectral features and their interaction with gabapentin is provided. The optimal conditions for sensing, including pH value, buffer volume, N-CQDs concentration, and incubation time, were established. The results showed excellent fluorescence quenching at 475 nm (λex = 380 nm) due to the dynamic quenching mechanism, and the sensor demonstrated excellent linearity in the 0.5-8.0 μg mL-1 concentration range with correlation coefficients of more than 0.999, a limit of detection (LOD) of 0.160 and limit of quantification (LOQ) of 0.480 μg mL-1. The accuracy of the proposed sensor was acceptable with a mean accuracy of 99.91 for gabapentin detection. In addition, precision values were within the acceptable range, with RSD% below 2% indicating good repeatability and reproducibility of the sensor. Selectivity was validated using common excipients and pooled plasma samples. The proposed sensor accurately estimated gabapentin concentration in commercial pharmaceutical formulations and spiked plasma samples, exhibiting excellent comparability with previously published methods. The 'greenness' of the sensing system was evaluated using the Analytical GREEnness calculator, revealing low environmental impact and strong alignment with green chemistry principles with a greenness score of 0.76. Thus, the developed N-CQDs-based sensor offers a promising, eco-friendly, and effective tool for gabapentin detection in various situations, ranging from clinical therapeutics to forensic science.

Exploring the role of copper and zinc in chronic otitis media: A novel spectrofluorometric method for precise determination and association study

Chronic otitis media is a common condition characterized by fluid accumulation in the middle ear, leading to a perforated eardrum and persistent middle ear drainage. Despite its impact on global health, the role of heavy metals, particularly copper and zinc, in its development and progression remains understudied. Herein, a spectrofluorometric method was developed for the precise determination of copper and zinc in human plasma samples and investigate their association with chronic otitis media. The method involves the use of the fluorescent probe 6,7-dihydroxy-4-phenylcoumarin to selectively quantify copper through fluorescence quenching and zinc through fluorescence enhancement with a remarked bathochromic shift. The method was validated and exhibited good linearity over a concentration range of 100-3000 ng/mL for copper and 200-5000 ng/mL for zinc. Application of the method to healthy volunteers and patients with chronic otitis media revealed significantly decreased copper and zinc levels in patients with chronic otitis media compared to the healthy individuals. These findings shed light on the involvement of copper and zinc in the pathogenesis of chronic otitis media and open avenues for additional treatment approaches.